This invention concerns utility valve boxes which typically house a shut off valve which are equipped with a locking cover which prevents opening of the cover so as to prevent unauthorized access to a utility shut off valves located in the valve box.
Valve boxes typically extend down into the ground to a varying depth with a shut off valve located below the locking cover. The shut off valve is provided to enable shutting off of service so as to enable maintenance or repairs to be carried out or to terminate service to a non paying customer.
It has become a common practice for unauthorized individuals such as occupants of a residence served by the utility to open the shut off valve after it has been closed by the utility company because of nonpayment of amounts due to the utility company.
Even worse, sometimes the valve box is filled with concrete to make it much more difficult for the utility to again shut off service and which entails a substantial expense for the utility.
Conventionally, a cover is installed over the top of the valve box which is secured in place by a threaded fastener which is configured to require a special wrench to remove the same so as to prevent unauthorized operation of the shut off valve. However, such special wrenches have become easily obtainable by members of the public since used by many utilities all over the country. Thus, requiring such a special wrench to remove the cover has become a relatively ineffective means to prevent unauthorized access to the shut off valve.
In recent years, specially configured bolt heads for securing valve box covers have been devised which require a wrench unique to each particular utility company which strictly controls the sale of these wrenches so that it is much more difficult for unauthorized persons to obtain such the wrenches now needed to remove a valve box cover.
These special wrenches are described in U.S. Pat. No. 9,708,714 issued to the present inventor which is hereby incorporated by reference.
However, even without having a special wrench an unauthorized person is able to pry off a cover to thereby enable access to the shut off valve below.
Another problem with some current designs is that they rely on springs to move cover locking elements back to a released condition. In the environment of curb and valve boxes, springs can often fail due to becoming rusted out or the locking elements can become jammed by ice or dirt and the locking elements cannot be released by the springs since the springs do not exert sufficient force on the locking elements to overcome such a jammed condition.
A similar problem is presented where water, dirt, rust and breakages can potentially cause other components of a lock mechanism to be rendered inoperable so as to incur significant expense by the utility in order to be able to remove the cover and access the shut off valve.
This is particularly a problem for security bolts which can be rendered inoperable by rusting of the threads thereof after a lengthy period since the least operation of the security bolt.
The present inventor has heretofore invented a locking cover intended for use with curb boxes as described in U.S. Pat. No. 9,708,714 referenced above. Curb boxes are substantially smaller in diameter than valve boxes which also do not usually have the internal flange used in the locking cover described in the aforementioned U.S. patent. That patented design is much more resistant to efforts to pry off curb box covers than conventional designs since it features a clamping arrangement which grips the internal flange to effectively resists removal of the cover by use of a pry tool.
It is an object of the present invention to provide a locking cover which is adapted to valve boxes and which does not require that the valve box have such an internal flange extending radially inward from the outer wall of the valve box in order to lock the cover.
It has also been found that if salt water gets into the threads of the security bolt and dries out to form crystals, this will interfere with proper rotation of the security bolt.
It is a further object of the invention to provide automatic lubrication so as to prevent interference in rotation of the threads of a security bolt particularly by salt crystals forming in the threads of the security bolt.
Another approach to protecting against unauthorized access to utility shut off valves is described in U.S. Pat. No. 7,870,867, in which a curb box lock mechanism is described which is not mounted to the cover. Rather, a blocking body separate from the cover is provided which is lowered down into the valve box to a location below the cover by use of a complex and unique tool which hold the blocking body in position within the curb box. The tool can also then be used to operate a lock mechanism in the blocking body to engage locking elements with inner surfaces of the curb box so as to be held securely in position within the curb box.
This approach is intended to prevent access to the shut off valve by prying off the cover since the blocking body is not attached to the cover and will continue to block access to the shut off valve even if the cover is successfully pried loose. The blocking body itself is not able to be pried loose due to its location down in the valve box which location prevents effective use of a pry tool.
However, it is necessary to fit the fixed blocking body within the curb box by upper and lower circular collars on the lock body which remain stationary while the lock mechanism is operated. The presence of the blocking body fixed in the curb box thereby prevents access to the shut off valve which is located below the blocking body.
However, there is a tendency for the blocking body to itself become stuck in the curb box as by ice, rust, mud, accumulated debris, etc. The special tool is relied on to engage the bolt and if the claws are stuck, the special tool may not be able to be turned sufficiently to retract the bolt and disengage the claws. Worse, even if the claws are able to be retracted, jamming in the pipe of the relatively closely fit collars of the blocking body with ice, rust or debris etc, may well make it difficult or impossible to remove the blocking body from the curb box since it is located well down in the curb box.
It is therefore another object of the present invention to provide a locking mechanism for a valve box cover which reduces the incidences of jammed condition of components down in the valve box such as can be caused by the presence of rust, ice, debris, etc., to make it possible to easily overcome any such jammed condition in the unlikely event it does occur.